/*
 * Copyright (c) 2007-2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: TreeWalker.java,v 1.2.4.1 2005/09/15 08:15:59 suresh_emailid Exp $
 */
package com.sun.org.apache.xml.internal.utils;

import com.sun.org.apache.xalan.internal.utils.SecuritySupport;
import java.io.File;

import org.w3c.dom.Comment;
import org.w3c.dom.Element;
import org.w3c.dom.EntityReference;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.ProcessingInstruction;
import org.w3c.dom.Text;

import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.ext.LexicalHandler;
import org.xml.sax.helpers.LocatorImpl;

/**
 * This class does a pre-order walk of the DOM tree, calling a ContentHandler
 * interface as it goes.
 * @xsl.usage advanced
 */

public class TreeWalker {

    /** Local reference to a ContentHandler          */
    private ContentHandler m_contentHandler = null;

    // ARGHH!!  JAXP Uses Xerces without setting the namespace processing to ON!
    // DOM2Helper m_dh = new DOM2Helper();

    /** DomHelper for this TreeWalker          */
    protected DOMHelper m_dh;

    /** Locator object for this TreeWalker          */
    private LocatorImpl m_locator = new LocatorImpl();

    /**
     * Get the ContentHandler used for the tree walk.
     *
     * @return the ContentHandler used for the tree walk
     */
    public ContentHandler getContentHandler() {
        return m_contentHandler;
    }

    /**
     * Get the ContentHandler used for the tree walk.
     *
     * @return the ContentHandler used for the tree walk
     */
    public void setContentHandler(ContentHandler ch) {
        m_contentHandler = ch;
    }

    /**
    * Constructor.
    * @param   contentHandler The implemention of the
    * @param   systemId System identifier for the document.
    * contentHandler operation (toXMLString, digest, ...)
    */
    public TreeWalker(ContentHandler contentHandler, DOMHelper dh, String systemId) {
        this.m_contentHandler = contentHandler;
        m_contentHandler.setDocumentLocator(m_locator);
        if (systemId != null)
            m_locator.setSystemId(systemId);
        else {
            try {
                // Bug see Bugzilla  26741
                m_locator.setSystemId(SecuritySupport.getSystemProperty("user.dir") + File.separator + "dummy.xsl");
            } catch (SecurityException se) {// user.dir not accessible from applet
            }
        }
        m_dh = dh;
    }

    /**
     * Constructor.
     * @param   contentHandler The implemention of the
     * contentHandler operation (toXMLString, digest, ...)
     */
    public TreeWalker(ContentHandler contentHandler, DOMHelper dh) {
        this.m_contentHandler = contentHandler;
        m_contentHandler.setDocumentLocator(m_locator);
        try {
            // Bug see Bugzilla  26741
            m_locator.setSystemId(SecuritySupport.getSystemProperty("user.dir") + File.separator + "dummy.xsl");
        } catch (SecurityException se) {// user.dir not accessible from applet
        }
        m_dh = dh;
    }

    /**
     * Constructor.
     * @param   contentHandler The implemention of the
     * contentHandler operation (toXMLString, digest, ...)
     */
    public TreeWalker(ContentHandler contentHandler) {
        this.m_contentHandler = contentHandler;
        if (m_contentHandler != null)
            m_contentHandler.setDocumentLocator(m_locator);
        try {
            // Bug see Bugzilla  26741
            m_locator.setSystemId(SecuritySupport.getSystemProperty("user.dir") + File.separator + "dummy.xsl");
        } catch (SecurityException se) {// user.dir not accessible from applet

        }
        m_dh = new DOM2Helper();
    }

    /**
     * Perform a pre-order traversal non-recursive style.
     *
     * Note that TreeWalker assumes that the subtree is intended to represent
     * a complete (though not necessarily well-formed) document and, during a
     * traversal, startDocument and endDocument will always be issued to the
     * SAX listener.
     *
     * @param pos Node in the tree where to start traversal
     *
     * @throws TransformerException
     */
    public void traverse(Node pos) throws org.xml.sax.SAXException {
        this.m_contentHandler.startDocument();

        traverseFragment(pos);

        this.m_contentHandler.endDocument();
    }

    /**
     * Perform a pre-order traversal non-recursive style.
     *
     * In contrast to the traverse() method this method will not issue
     * startDocument() and endDocument() events to the SAX listener.
     *
     * @param pos Node in the tree where to start traversal
     *
     * @throws TransformerException
     */
    public void traverseFragment(Node pos) throws org.xml.sax.SAXException {
        Node top = pos;

        while (null != pos) {
            startNode(pos);

            Node nextNode = pos.getFirstChild();

            while (null == nextNode) {
                endNode(pos);

                if (top.equals(pos))
                    break;

                nextNode = pos.getNextSibling();

                if (null == nextNode) {
                    pos = pos.getParentNode();

                    if ((null == pos) || (top.equals(pos))) {
                        if (null != pos)
                            endNode(pos);

                        nextNode = null;

                        break;
                    }
                }
            }

            pos = nextNode;
        }
    }

    /**
     * Perform a pre-order traversal non-recursive style.
    
     * Note that TreeWalker assumes that the subtree is intended to represent
     * a complete (though not necessarily well-formed) document and, during a
     * traversal, startDocument and endDocument will always be issued to the
     * SAX listener.
     *
     * @param pos Node in the tree where to start traversal
     * @param top Node in the tree where to end traversal
     *
     * @throws TransformerException
     */
    public void traverse(Node pos, Node top) throws org.xml.sax.SAXException {

        this.m_contentHandler.startDocument();

        while (null != pos) {
            startNode(pos);

            Node nextNode = pos.getFirstChild();

            while (null == nextNode) {
                endNode(pos);

                if ((null != top) && top.equals(pos))
                    break;

                nextNode = pos.getNextSibling();

                if (null == nextNode) {
                    pos = pos.getParentNode();

                    if ((null == pos) || ((null != top) && top.equals(pos))) {
                        nextNode = null;

                        break;
                    }
                }
            }

            pos = nextNode;
        }
        this.m_contentHandler.endDocument();
    }

    /** Flag indicating whether following text to be processed is raw text          */
    boolean nextIsRaw = false;

    /**
     * Optimized dispatch of characters.
     */
    private final void dispatachChars(Node node) throws org.xml.sax.SAXException {
        if (m_contentHandler instanceof com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTM.CharacterNodeHandler) {
            ((com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTM.CharacterNodeHandler) m_contentHandler).characters(node);
        } else {
            String data = ((Text) node).getData();
            this.m_contentHandler.characters(data.toCharArray(), 0, data.length());
        }
    }

    /**
     * Start processing given node
     *
     *
     * @param node Node to process
     *
     * @throws org.xml.sax.SAXException
     */
    protected void startNode(Node node) throws org.xml.sax.SAXException {

        if (m_contentHandler instanceof NodeConsumer) {
            ((NodeConsumer) m_contentHandler).setOriginatingNode(node);
        }

        if (node instanceof Locator) {
            Locator loc = (Locator) node;
            m_locator.setColumnNumber(loc.getColumnNumber());
            m_locator.setLineNumber(loc.getLineNumber());
            m_locator.setPublicId(loc.getPublicId());
            m_locator.setSystemId(loc.getSystemId());
        } else {
            m_locator.setColumnNumber(0);
            m_locator.setLineNumber(0);
        }

        switch (node.getNodeType()) {
            case Node.COMMENT_NODE: {
                String data = ((Comment) node).getData();

                if (m_contentHandler instanceof LexicalHandler) {
                    LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

                    lh.comment(data.toCharArray(), 0, data.length());
                }
            }
                break;
            case Node.DOCUMENT_FRAGMENT_NODE:

                // ??;
                break;
            case Node.DOCUMENT_NODE:

                break;
            case Node.ELEMENT_NODE:
                NamedNodeMap atts = ((Element) node).getAttributes();
                int nAttrs = atts.getLength();
                // System.out.println("TreeWalker#startNode: "+node.getNodeName());

                for (int i = 0; i < nAttrs; i++) {
                    Node attr = atts.item(i);
                    String attrName = attr.getNodeName();

                    // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());
                    if (attrName.equals("xmlns") || attrName.startsWith("xmlns:")) {
                        // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());
                        int index;
                        // Use "" instead of null, as Xerces likes "" for the
                        // name of the default namespace.  Fix attributed
                        // to "Steven Murray" <smurray@ebt.com>.
                        String prefix = (index = attrName.indexOf(":")) < 0 ? "" : attrName.substring(index + 1);

                        this.m_contentHandler.startPrefixMapping(prefix, attr.getNodeValue());
                    }

                }

                // System.out.println("m_dh.getNamespaceOfNode(node): "+m_dh.getNamespaceOfNode(node));
                // System.out.println("m_dh.getLocalNameOfNode(node): "+m_dh.getLocalNameOfNode(node));
                String ns = m_dh.getNamespaceOfNode(node);
                if (null == ns)
                    ns = "";
                this.m_contentHandler.startElement(ns, m_dh.getLocalNameOfNode(node), node.getNodeName(), new AttList(atts, m_dh));
                break;
            case Node.PROCESSING_INSTRUCTION_NODE: {
                ProcessingInstruction pi = (ProcessingInstruction) node;
                String name = pi.getNodeName();

                // String data = pi.getData();
                if (name.equals("xslt-next-is-raw")) {
                    nextIsRaw = true;
                } else {
                    this.m_contentHandler.processingInstruction(pi.getNodeName(), pi.getData());
                }
            }
                break;
            case Node.CDATA_SECTION_NODE: {
                boolean isLexH = (m_contentHandler instanceof LexicalHandler);
                LexicalHandler lh = isLexH ? ((LexicalHandler) this.m_contentHandler) : null;

                if (isLexH) {
                    lh.startCDATA();
                }

                dispatachChars(node);

                {
                    if (isLexH) {
                        lh.endCDATA();
                    }
                }
            }
                break;
            case Node.TEXT_NODE: {
                //String data = ((Text) node).getData();

                if (nextIsRaw) {
                    nextIsRaw = false;

                    m_contentHandler.processingInstruction(javax.xml.transform.Result.PI_DISABLE_OUTPUT_ESCAPING, "");
                    dispatachChars(node);
                    m_contentHandler.processingInstruction(javax.xml.transform.Result.PI_ENABLE_OUTPUT_ESCAPING, "");
                } else {
                    dispatachChars(node);
                }
            }
                break;
            case Node.ENTITY_REFERENCE_NODE: {
                EntityReference eref = (EntityReference) node;

                if (m_contentHandler instanceof LexicalHandler) {
                    ((LexicalHandler) this.m_contentHandler).startEntity(eref.getNodeName());
                } else {

                    // warning("Can not output entity to a pure SAX ContentHandler");
                }
            }
                break;
            default:
        }
    }

    /**
     * End processing of given node
     *
     *
     * @param node Node we just finished processing
     *
     * @throws org.xml.sax.SAXException
     */
    protected void endNode(Node node) throws org.xml.sax.SAXException {

        switch (node.getNodeType()) {
            case Node.DOCUMENT_NODE:
                break;

            case Node.ELEMENT_NODE:
                String ns = m_dh.getNamespaceOfNode(node);
                if (null == ns)
                    ns = "";
                this.m_contentHandler.endElement(ns, m_dh.getLocalNameOfNode(node), node.getNodeName());

                NamedNodeMap atts = ((Element) node).getAttributes();
                int nAttrs = atts.getLength();

                for (int i = 0; i < nAttrs; i++) {
                    Node attr = atts.item(i);
                    String attrName = attr.getNodeName();

                    if (attrName.equals("xmlns") || attrName.startsWith("xmlns:")) {
                        int index;
                        // Use "" instead of null, as Xerces likes "" for the
                        // name of the default namespace.  Fix attributed
                        // to "Steven Murray" <smurray@ebt.com>.
                        String prefix = (index = attrName.indexOf(":")) < 0 ? "" : attrName.substring(index + 1);

                        this.m_contentHandler.endPrefixMapping(prefix);
                    }
                }
                break;
            case Node.CDATA_SECTION_NODE:
                break;
            case Node.ENTITY_REFERENCE_NODE: {
                EntityReference eref = (EntityReference) node;

                if (m_contentHandler instanceof LexicalHandler) {
                    LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

                    lh.endEntity(eref.getNodeName());
                }
            }
                break;
            default:
        }
    }
} //TreeWalker
